The anime’s story revolves around Nyaa-tan, the cat of Chinese astrology who wants to become a member of the Chinese zodiac. Nyaa-tan is simple and suffers from memory loss, and she tries various foolish ways to become a member. She meets Takeru Amato, a high school student who lives alone in Akihabara, and becomes a freeloader at his house. Little by little, she gets closer to her goal.